MikroTik

Hi,

I have a RB433A device with RouterOS 5.11. I have been running SSTP (with RADIUS auth) successfully for a while now, everything was OK until recently, when my wife (we both have Windows 7) could not establish SSTP VPN any more. She would get the error, shown in this screenshot:
On RB433A, the this error is shown in the debug sstp log:
For me, SSTP is established fine. 2 other remote workers also have the same problem as my wife (we all use Windows 7). The certificate is valid for another month or so. My wife and I establish VPN from the same local network over the internet to the RB433A device.

Any ideas? I Wiresharked both TCP sessions of connection establishment, however the SSL error is sent encrypted back from the server, so I can't read it. Perhaps I'll try with ssldump to see what actually is sent over by the server to the failing clients.

However, can anybody help me with the "recvd too small packet" error?

Thanks,
Nejc

I got the same problem, but the windows error code is 631, I'm looking for how to solve too.

I have exactly the same issue with windows error 631.

RB750 ROS 5.11 - the same issue
RB750G ROS 5.11 - the same issue
RB433AH ROS 5.11 - the same issue

Clients are Windows 7 x64 SP1 with latest patches.

Its not issue of clients, because SSTP connection to other VPN server (Windows Server 2008 R2 with RRAS) function correctly.

I also have the same issue. First time I used it since upgrading to 5.11 from 5.9.
Running RB493G

I have the exact same problem, tried adding sstp user manually to no avail.

Same issue here, tried adding sstp user manually, using RB1100 + RouterOS 5.11.

I think there is a problem with some Windows 7 update.
I have the same problem on upgraded Windows 7 Ultimate, when on secondary netbook I can connect to SSTP without a problem.

I will install waiting updates one by one - and try detect which give a problem

I found
There is an update KB2585542 (http://support.microsoft.com/kb/2585542) which fix some issues in SSL.

There is an explanation of problem and suggested fixes (editing Registry ;-( )
http://social.technet.microsoft.com/For ... 3fd2ff4931

maybe some one in MikroTik team will found a better solution.

Bygger This update is all security fix for ssl and tls itself from what I understand. So there should be att simular fix for mikrotik!

Sent from my Galaxy Nexus using Tapatalk

I confirming, that source of troubles is MS Patch KB2585542.

When i uninstall this patch, Mikrotik SSTP works great.

After that, i install this patch again, and try to add registry key (HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\SecurityProviders\SCHANNEL\SendExtraRecord - 2). Well, Mikrotik SSTP vpn works again great.

Regedit hack works for me too. Thanks!

Nejc

The update was aimed to correct issues with tls and ssl. If Microsoft have corrected this shouldn't mikrotik do the same?

Sent from my Galaxy Nexus using Tapatalk

The update was aimed to correct issues with tls and ssl. If Microsoft have corrected this shouldn't mikrotik do the same?

Sent from my Galaxy Nexus using Tapatalk

Definitely yes, but this is a function fix till Mikrotik will release corrected ROS.

After added the regedit, SSTP work again!!

Thanks a lot!

I have the same issue (too small packet) (windows error 631) event with RouterOS 5.12.
... going to try the registry fix.

Ah thanks that was driving me nuts, was trying to figure out what i'd done to my laptop to break SSTP seeing as it had worked the last time I'd used it and was working fine between routerboards.

What about Mikrotik ROS developers? Are you guys going to fix this issue in next version? We need the fix ASAP.

Thanks!

We have found ad fixed the problem. Please wait for v5.13 release.

FYI, I have confirmed that this bug is back in Windows 8.1 and ROS 6.1. Adding SendExtraRecord with with a hexadecimal base value of 2, the problem is resolved.

I have to confirm this bug too, don't know if it is RouterOS or MS bug this time:
server - ROS 6.3
clients - W2012 R2

Adding registry key helped me too.

Radek

I had the same issue on my Windows RT 8.1... adding the registry entry also solved it.

Reading http://support.microsoft.com/kb/2643584 it however means that the SSTP implementation is flawed on RouterOS.

Our Windows 8.1 clients also needed this registry addition to fix this one.

Currently ROS uses TSL v1.0.
We will look into this issue and upgrade to newer TLS version.

Same here, added registry fix for windows 8.1.

Registry fix did not solve the problem for my user who upgraded to windows 8.1. I guess there is something more that has to be fixed when using radius for authentication?
(pptp also fail to authenticate using radius, and the router never send auth-packets to the radius server, neigther for pptp nor sstp. Both pptp and sstp works with radius when client is win7/win8.0)

Petterg. I'm using sstp and radius for auth and 8.1 clients are connecting fine (after registry fix)

Sent from my GT-I9100 using Tapatalk now Free

Excellent review here. I definitely agree with all your points Alan. Good job!

A little update here as the registerfix didn't work for one of my users.
The next time I had the users pc on my hands I searched through the registry for keys named "SCHANNEL" and added the key value to all the hits I got. That solved the problem. The search got 4-5 hits. I don't know which key did the trick.

I can confirm that the registry change worked for me as well - a first time setup with a test user (Win8.1).

I will read up on the links you all so kindly passed on in the thread, but perhaps someone could share their opinion on the implications of making the required change to the registry (i.e Beast vuln?). Also, has the change to other TLS version made its way into the product's roadmap?

On a separate note, how do I enable the debug logging for sstp connections as seen in the original post?

Fredrik

bad news.. updated win7 win8 and win 8.1 Now all are affected with this error. not so goo to tell client why vpn not work.. and to all say whats need registry fix...

so i hope what this would bee resolved near top 1 in bugtracked

Hi all,
I tried to update to v6.10. I removed registry key (described above) on Windows 7/2008 and tried to connect to Mikrotik SSTP VPN. It worked - but ended up with a different error.

Error 734: The PPP link control protocol was terminated.

With try&mistake approach I found out that if I changed "Use encryption" in PPP profile from "required" to "yes" on my Mikrotik, VPN was successfully connected.

Can anybody else confirm?

to solve this problem just edit regedit on every client pc

HKEY_LOCAL_MACHINE \ System \ CurrentControlSet \ Control \ SecurityProviders \ SCHANNEL \ SendExtraRecord = 2

use DWORD 32bit

it works for me

Unfortunately, but registry hack does not work for me (I'm check this record few times)

Trying on
RB2011xx with RoS 5.24 & 5.26
Windows 8.1 with all current updates
Result:
on Windows - Error 631
On RoS: rcvd too small packet

Now, only ONE client has this problem - my personal ultrabook. =(

Any ideas?

PS. Also, I try uncheck "use TLS 1.1/1.2" in IE options - no result

Changed "Use encryption" in PPP profile from "required" to "yes" on your Mikrotik, VPN from Win8.1 will be successfully connected.

I verified it once again today. I wasn't able to connect from fully patched Win8.1 (including spring update) to Mikrotik SSTP VPN (ROS 6.6). First of all I upgraded Mikrotik to the latest 6.12. I checked there is no regedit fix on my Win8.1. Then I changed "Use encryption" from "required" to "yes" in Mikrotik's PPP profile and I was able to connect from Win8.1 immediately.